Abstract: In order to study the influence of the chute on the particle size segregation during the discharging process of a bell-less top blast furnace, this paper uses the discrete element method (DEM) to simulate the discharging process, and obtain the velocity field of particles on the chute and the particle size distribution in both radial and circumferential directions. In addition, the influences of the key slots on the inner surface of the chute, the section area shape and the tilting angle of the chute on the particle size segregation are analyzed. It is shown that (1) the keyslots on the inner surface of the chute cause a circumferential particle size segregation; (2) a square section area is better than a circle one for it facilitates an accurate radial particle distribution; (3) the tilting angle of the chute influences the radial particle size segregation. This study provides a theoretical basis for the design of blast furnace discharging process and the control of the burden distribution.